Pneumatic thread control system for looms



March 18, 1952 y v. F. sEPAvlcH PNEUMATIC THREAD CONTROL SYSTEM FOR LOOMS Filed Oct. 11, 1950 Patented Mar. 18, 1952 ,lJNIfrEoN STATES," PATENT OFFYICE;

PNEUMATIC THREAD CONTROL SYSTEM FoRLooMs Victor F. Sepavich, Worcester, Mass., assigner to l Crompton & Knowles LooniWorkS, Worcester, f j

Mass., a corporation-of `Massachusetts Application Octoberv'llv, 1950, Serial No. 189,555

' 167 claims-. (crise-336.4)

This invention relates to pneumatic thread control systems of means for weft replenishing looms and itis the general object of the invenv tion to provide means either to give a signal or effect loom stoppage upon failure of the pneu- Vmatic system. I

A form of thread control system for werft replenishing looms which has gone into extensive use employs a pneumatic thread holder to tension the weft ends of reserve bobbins in the magazine, and also employs a collector for. the

Waste threadsy left by the outgoing and incoming bobbins. within the collector the latter is generally provided with a screen which may become sufliciently cloggedv by the waste threads to prevent creation of a sufcient partial vacuum within the system for correct operation. t Y.

It is an importantobject of the present invention to provide a pneumatically controlled electric switch which upon'closure canv either give a signal, such as the illumination of a lamp, or effeet loom stoppage. The switch is associated with a bellows unit connected through a. small leak vent to the interior of the pneumatic system. So long as adequate subatmospheric pres- ""In vorder that accumulated threads within the collector may beremoved a door or cap or the like is provided Ywhich may be opened temporarily to 'afford access lto the interior of the collector. If by oversight the cover should not-be re'- turned to its closed position subatmospheric pressures will not be developed within the container and in this event the bellows unit will operate to close vthe switch. If the switch controls a circuit containing a lamp the latter will remain illuminated and thus attract attention of the weaver who will then close the cover.

.Ordinarily the drop in effective pressure within the system mayy not be sufcient to justify loom stoppage; in which event a signal will suf- .ce, but if desired the switch can also cause loom stoppage.

With these and other objects in view which will appear as the description proceeds, the invenf tion resides in the combination andarrangement -of parts hereinafter described and set forth.

4 In the accompanying drawings, wherein a con In order to coniine the threads .thread collector.

-it is desired to operate the loom.

. 2 n Fig; .1 shows a side elevation of a weft replenf lishing loom having the invention applied. there: to, j

Fig. 2 is an enlarged plan view looking inthe .direction of arrow 2, Fig. l, Fig. 3 is an enlarged vertical section on line .3 -`3, Fig. 2, L 1 y Figs. 4 and 5'. are vertical sectionson lines .4 4 and 5-5, respectively, Fig. 3.,

Fig. 6 is a section on line. 6- S,'F 1g. Fig. 'l is an elevationof the switch'carrier loolging in the direction of arrow 1, Fig.

Fig. 8 is a diagrammatic view of an electric circuit which can be vused with the invention, .and

Fig. 9 is a diagrammatic plan view showing the -manner of pneumatically connecting and dis; connecting the thread holderfrelative to the Referring to Fig. 1, the lloom frame .ports top and bottom shafts 2.and 3. connected byl gears 4 and 5 the latter of which may betwice the diameter of the formen. A'driving' gear Clutch mechanism not shown herein is employed to connect the gear 6 to the top shaft 2 when A form of continuously operating. pump I0 serving as a source of subatmospheric, pressures is mounted in fixed position on, a .stand II sup:

ported by the loom frame and is driven bythe Hiblelspipe I2..in which subatmospheric'-pressures f varecreated bythe pump. Hose I2 extendsprwardly and is connected to a hollow thread. collector designated generally a't ,(.'f.vv

. yAs shownin the present instance the .comprises a head I5, an l elongated generally transparent hollow cylinder I6, and a cap or cover .I'I. Ihe latter is mounted on lever.A I8 moving about a iixed pivot lI!) and held normally'inthe `closed position shown in Fig. 2 by a spring v2Il.

The head is associated with a pneumatic thread holder H for. the weft ends W which extend'from .tionary type, but the invention is not limtedlto this form of magazine.

- The holder is pneumaticallyv connected to .interior of the. container C at regularv intervals 'by" means pf a llever 25 pivotedas at 1.26 tothe head I5. This lever is connected by rearwardly .extending rodj'Zl to. lanother Vlever v 128; rocking abyzint'a'fixedY pivot.29. A roll 30- at the loottor'n` of venient embodiment of the'inventionis set forth:. ojlever is moved to the left, Fig.A L-by a cam 3| secured to the top or crank shaft 2, once for each pick of the loom, to move the rod 21 rearwardly. A compression spring 32 interposed between the head I and the lever 25 normally rocks Vthe latter and the rod 21 forwardly, or to the left as viewed in Fig. 2. An elasti tube 33 made forV instance "of soft rubber connects the holder H pneumatically to the interior ofv collector C-and extends along a wall 34 forming part of head I5. An arm 35 of lever 25 is normally held by spring 32 against tube 33 to squeeze ity against wall 34, see full lines in Figs. 3 and 9,1 to pinch the weft threads W passingintothe tube.

When the lever 25`is in its normal position, as shown in full lines in Fig. 9, the threadholder- The matter thus far described may be of usual ccnstruction'and of itself forms no part of the will be pneumatically disconnected from the interior of the container Cl and during this time the pump can create or build up subatrnospheric pressures within the container. ofthe loom, however, upon rocking of lever 2 5 to the., dotted. line position shown in Fis. 9', the.

. fortlr in prior Patent No. 2,431,556 issuedV to lflooperet. al. The/.head I5v is .supported by a bracket 35 to a stationary parti of the loom. as by boltsv 31'., and

is provided with an air chamber 38'.

A lug 49 'extending upwardly from the head l5, is connected to a nexible hose 4I leading to approved; form of pneumatic thread remover locotodbetween themas'azine and the fabric beingwoven. The remover is not shown herein but mayY for instance be made as set forth in prior Patent, No, 2,219,163 issued to Darwin.

During loom,v Operation subatmospheric pressures will be built up within the container due to operation of rthe pump It, and when the lever 2-.5 is turned in a clockwise direction as viewed in Fig.l 2' fromits normal position due to cam 3 I, any.V loosel waste threads remaining incident to a weft replenishing operation will be drawn from the, thread holder' and remover into the containcr.` The weft ends W will also b e tensioned. Asset; forth herein the hose 4I is not controlled by. the, lever 25 and anythread coming under control ofthe thread remover will be drawn immediatelyv into the 'container without regard to the.. position of lever A25. The thread remover willordinarily require a smaller stream of air thanthat required by the holder and it can thereiore be .connected directly to the interior of the oontaineit..

The weft ends and waste threads which enter they container willV be attracted toward the cover L1. The .latter is made with a cavity ccmmunicating at one side thereofy with ametal tube 46. connected to the hose I2. Extending across the other side of the cavity is a screen 41' against which the, threads are drawn. When a large numbers of threads accumulate on the screen l 41 there will be a. drop in the eiective pressures Within. that part of the Container to the left-0f the cap or cover I1 as4 viewed in Fig. 2. .Under these ccnfditions the pneumatic system may'fail to operate and the present invention provide 'means 'which will Vcall attention vto such failure.

At each pick i present invention except as noted hereinafter.

The head I5 has a wall 50 into which is threaded the stem 5I of a bellows unit or pneumatic electric switch controller designated generally at B. The stem has a small' leak vent 52 which communicates with the interior of a thin sheet metal resilient bellows 53 closed by an end wall 54. The stem 5I has a flange 55 which is s ecnred by screws `56 t0 a retainer 5'?.

A switch carrier 60 made preferably of insulating material is held to the retainer by screws 5I and contains a. normally open electric switch designated genelally at S. As shown in Fig. 5

this switch has a contact 62 one end of which is fixed as at 53 to the carrier. Contact 62 is electrically connected to a bar 65 on the outer face of .the carrier. cally to the retainer, which is metal, by one of the screws 5I', and in this way the con-tact 52 is.

erounded to the loom- The switch S has a secondcontact 61' having a centrall prong 68 vheld to a stationary clip 69. Contact 61 also has resilient arms 10 which fit into angles 1I o f a resilient operatorv 12 the lower the outer face of the carrier. This latter contact as well as the contact61 is insulated bythe carrier. Y

The resilient operatorl has a small button 15 which, isy in position for Yengagement with the end wall 54 of the bellows. The switch Vis normally onen with the contact 61 out (af-engagement withl the contact 62, but when the button 15v is pressed to the right as viewed in Fig. 3y a snap action of contact 61 occurs moving itaway Vfrom its adi usting screw 16 into engagement with the contact 62. The latterphas an adjusting screw 11. While a specific form of electrica switch hasA been described the invention is not' limited to such a switch, and` it willbe. suflicient for the purposes of the invention if movement of wall 54 effects closure ofy any suitable switch.

A thin metal case 80 in the form of a cylinder is secured to the carrier as at 8| and has mounted thereon a lamp structure L containing a lamp 82 which is normally extinguished.

Solong as properY subatmospheric pressures exist within the collector C. the bellows unit will be contracted due to its communication with the interior ofthe collector through the leak vent 52 and the pneumatic controiler B will permit switch S to remain open. If for.. any` reason inadequatepressures should exist within the collector for any appreciable length ofl time they will be ccmn'iunicated through thev vent 52 to the interior of the bellows unit and the latter will expand because ofits resilience andl cause end wall 54 to press on button 15 sufficiently to close switch S. When this happens the bellows and switch, acting as a pneumatically controlled circuit closing means responsive to pressures withclosure' ofthe switch is longer thanthe interval during which the holder Vand collector will be pneumatically connectedL due to rocking of lever 25. Y

This baris connected electria contact.93 in engagement with a switch blade 94. controlled by the shipper handle 95. Blade 94 is connected to the secondary 96 of a transformer T and the secondary is grounded by Wire 9'|.

When the shipper handle is in the loom driving position shown in Fig. 8 blade 94 will engage contact 93 and the lamp can be illuminated to give a visual signal whenever switch S is closed., When the shipper handle is in the stopping position, or to the right of. that shown in Fig. 8, closure of switch S will not illuminate the lamp 82. Switch S is likely to be closed during an extended period of4 stoppage of the loom due to leakage of air throughout the vent 52, but this will not result in continued illumination of the lamp.

When the weaver opens the cover 'l and moves it to the dotted line position indicated in Fig. 2 for removal of accumulated threads within the container there will be an immediate neutralization of the subatmospheric pressures within the container and the bellows unit will close switch S. It the weaver should leave the cover in its open position the lamp 82 will continue to burn and in doing so will call attention to the fact that the cover has not been properly closed.

vIn some instances it may be desirable to stop the loom in the event of failure of the vacuum system, and when this is desired a solenoid |00 may be used. As shown herein the solenoid is in parallel with the lamp 82, but if desired it can be used instead of the lamp.- This solenoid may be part of a well-known knock-off mechanism more generally associated with electric warp stop motions. The knock-off mechanism includes a .lever 0| rocked by a cam |02 on the bottom shaft 3, a link |03 the vertical position of which is controlled by the solenoid, a lever |04 pivoted to the link, and a rod |05 connected to the shinper handle 95. Energization of the solenoid |00 will lift the link and enable rocking of lever |01 in a counter-clockwise direction as viewed in Fig. 1 to rock the shipper handle to effect loom stoppage. Ordinarily this stopping will not be desired, but where it is employed the vent 52 may be quite small to require a. considerable length of time for expansion of the bellows unit, during which time it will ordinarily be possible to lopen the cover, remove the contents of the con- .tainer C, and close the cover before the bellows Scan. expand sufficiently to close switch S.

From the foregoing it will be seen that thev A 'proper subatmospheric pressures .will result in .closure of a switch in an electric circuit containting either a lamp, or solenoid |00. or both. Mo-

'mentary reduction of pressure within collector C due to rocking of lever 25 will not afford enough time for suiiicient air to pass through duct 52 to effect closure of the switch. While the principalrefason for failure of the pneumatic system 'is likely to be due to accumulation of weft ends 'or waste threads on the sieve or "screen 41, it

collectors have beenshown for illustrative p urposes, "the invention is not limited to such forms,

wherein failure of the system for any apprecl-i "able length of time can be relied upon to permit egrpansion of the bellows unit with resultant closure of switch S. The system as set forth herein applied both to the thread holder H and a l"thread removing mechanism not shown but supplied with subatmospheric pressures through the pipe 4 I.

@Having thus described the invention it will be seen that changes and modications of the fore- .g'oing specific disclosure may be made without r4' d e1 3arting from the spirit and scope of the invention;

What is claimed as new is: y 1. In a pneumatic thread control means for the reserve bobbin weft ends of a loom having a source of subatmospheric pressures and a nor- .'.mally open electric circuit to be closed upon l create subatmospheric pressures in said system to fcauseclosure of said electric circuit;

2. In a pneumatic thread control means for the removal of waste threads from a loom having a source of subatmospheric pressures and a normally open electric circuit to be closed upon failure of the control means, a pneumatic syste'm in which subatmospheric pressures are created by said source to effect removal of said waste threads, and pneumatically controlled closing means for said electric circuit responsive to vpressures within said system and effective to close said electric circuit upon failure of said control means due to inability of said source `to create subatmospheric pressures in said system.

3. In a pneumatic thread control means for the removal of waste threads from a loom having a source of subatmospheric pressures and a norvmally open .electric circuit to be closed upon failure of the control means, a pneumatic system in which subatmospheric pressures are "created by said source and into which the waste threads are drawn due to said pressures, sa-id waste threads due to accumulation thereof with# in the system tending to prevent creation of Asubatmospheric pressures within the system by (said source, and pneumatically controlled clos- .Y ing means for said electric circuit responsive to "pressures within said system and effective to 1.close said circuit when accumulated waste threads in the system causes failure of said conftrol means by preventing the creation' in said sys- 4 tern of subatmospheric pressures by s`aid source.

4. In a pneumatic thread control means for a loom having weft ends leading from reserve .fbobbins anda normally open electric circuit to ffbe closed upon failure of the control means, "a pneumatic thread holder for the weft endsfa f source of subatmospheric pressures, a hollow thread collector pneumatically connected to the holder and source and in which subatmopheric pressures are created by said sourceto draw the weft ends from the holder into the collector. a "normally open electric switch in said electric cirwill be apparent that failure of the pump or the I "hose |,2` will also eect closing of switch S. While specific `forms of vpneumatic thread holders and cuit, and a pneumatic controller for the switch f gin pneumatic communication with the 4collector and effective to maintain the switch in open con- ,.jidition ifv subatmospheric pressures exist within ""the collector but effective to close said switch vbut can ce-used in any thread control system 'nipon failure of said control means, due to incpsasye ability of! said. source to create subatmospheric pressures within the-collector. y

5. Ina pneumatic threadcontrol means for a loom. having weft ends leading from. reserve bobbins and` a normally open electric circuit to be closed. upon failure of theA control means, a source of subatmosphericpressures, a pneumatic thread holder for the weft ends, a pneumatic system pneumatically connecting said sourceA to said holder eiective when the system is operatingl properly to enable said source to create. subatmospheric pressures inthe holder, a normally open electric switch in said circuit, and a pneu-v matic controller for said electric switch responsive to pneumatic pressures in said system and effective to close said s witch and circuit upon failure of the control means due to inability o said source to maintain subatmospheric pressures inV said system.

- 6. In a pneumatic waste thread removal means for. a loom having a normally open electric circuit to' be, closed upon failure of the removal means, a source of subatmospheric pressures, a pneumatic waste thread removing systemY pneumatically connected to said source effective. to drawwaste threads from the loom into the system, a normally open electric switch in said circuit, a pneumatic controller for the switch responsive to subatmospheric pressures. in said system, and a screen in said; system intermediate the controller and said source to prevent threads. drawn into the system from reaching said source, thewastethreads due to accumula,- tion on the screen tending to prevent the: creation. il subatmospheric pressures by saidsource in the system beyond said screen with reference to saidy source, said controller operating. to'cl'ose said switch and circuit upon failure. of said removal means. due to inability of saidusource. to create. subatmosphericpressuresV in= the system becauseof the accumulation of. wastey threads; on the screen.4

7. In a pneumatic thread controlmeansfor aloom having a normally open electric circuit effective upon closure to indicate failureof the control means, a source of subatmospheric pressures, a pneumatic thread holder, a system. pneumatically connecting the thread holder andthe source, a pneumatic thread collector in said system intermediate the holder and source, a normally open electric switch in said circuit, and a controller for the switch in pneumatic. com munication with the system intermediate the holder and source e'ective upon failure of subatmospheric pressures in. said collector to close said switch and circuit.

8. In a pneumatic waste thread cont-rol means for a loom having reserve bobbin. weft. endsand a normally open electric circuit effectiveaupon closure to indicate failure of the control. means, a source of subatmospheric pressures, a pneumatic thread holder for the weft. ends, a pneumatic system pneumatically connecting the source and holder to create subatmospheric pressures in the latter, a waste thread. collector in the system provided with a screen intermediate said source and holder, and means responsive. to pneumatic pressures inthe system effective upon failure ofi subatmospheric pressures. in said system between the holder and screen dueto accumulation on. the latter of' waste threads to effect closure of said' circuit.

9. In a, pneumatic waste threadconti'ol means for a loom hav-ing a normally open electric circuit ei'ective uponn closure to indicate failure of the.. control means. aY source of subatmospheric pressures, aA pneumatic, collector for the, waste threads, a` system pneumatically .connecting the source to. said collector creating subatmospheric pressures-inthe latter to draw waste threads" intothecollector, a cover for said collector normally closed but operable to permit removal'V of waste threads from the collector;Y a normally open electric switch in said circuit, and a pneumatic controller for the switch in communication with the system effective to close said switchand" circuit uponfailure of the control means to create: subatmospheric pressures in said collector due to opening of. said cover.

I0'. The structure set forth in claim' 9 wherein said cover is ,provided with a screen againstwhich the waste threads in the collector arefpnexrmatically drawn.

11'.. In a pneumatic control meansfor the waste threads of. a loom having, a normally open; electric circuit. containing a lamp, a source of subatmospheric pressures, a collector fory the waste threads pneumatically connected to and having subatmospheric pressures created therein by said source,. and, a pneumatically controlled closing means for said circuit responsiveto pneumatic pressures within said collector normally maintaining the circuit` open during theA existencey of subatmospheric pressures withiny said collector but effective upon non-existence of subatmospheric pressures in said collector to close said circuit and cause illumination of said lamp.

12. In a pneumatic control means" fcrf the reserve' bobbin weft endsVV and" waste threads of a loom provided with aV normally open electric circuit which when closed' gives a visual signal, a pneumaticA thread' holder for the weft ends; a thread collector for the waste threads, a source of subatmosphericpressures' pneumatically connected to the thread holderzt'o drawthe weft ends thereinto and also pneumatically connected" to the collector to draw the waste threads thereinto, and circuit closingv means for said circuit responsivev to pneumaticv pressures in said collector maintaining the circuit open when subatmospheric pressures exist within the thread holder and collector but effective upon the nonexistence of subatmospheric pressures in said thread holder and collector to close said circuit to energize said visual signal.

13. In a pneumatic control means for thereserve bobbin weft ends of a loom provided with a normally open circuit capable upon closure of giving a visual signal, a source of Vsubatmospheric pressures, a pneumatic system for the weft'end's in which subatmospheric pressures are created by said source to tension said weft ends, and pneumatically controlled circuit closing means for said circuit responsive to pneumatic pressures within the system effective tomaintain said circuit open when subatmospheric pressures are created by said source within said system but eifective to close said circuit upon failure of said source to create subatmospheric pressures within said system.

14. In pneumatic thread contro1l-means for the reserve bobbin weft'. ends. of. a, loom, whichA is stopped upon energization ofi a solenoid due to closure of a normally open electric circuit,y a source. of subatmosphericpressures, a. pneumatic system for the. weftends inwhichsubatmospheric pressures. are created by said source to tension said weft ends, and. pneumatically-v controlled closing means Vfor said circuit. normally effective to maintainy the. circuit open when said source maintains subatmospheric pressures within"'the system but eiective upon failure of said sourceto. maintain said subatmospheric pressures in vsaid system to close said circuit and effect stoppage of the loom. f 15. In a, pneumatic thread control means for the reserve bobbin weft ends of a loom havnga source of subatmospheric pressures and aA n or-v mally open electric circuit to be closed` upon failure of the control means, a pneumatic thread collector pneumatically connected to saidsource and having subatmospheric pressures created therein vby said source, a pneumatic thread holder for the weft ends normally pneumatically disconnected from the collector but periodically connectedpneumatically to the collector for brief intervals, ahormally open electric switchain said circuit, and a, controller for said switch res'pQn sive to Vsubatmospheric pressures and communieating with said collector and operative to-close said switchl upon failure of the contro1 means due to. absence of subatmospheric pressures within said container for a period of time greater than one of said intervals.

16. In a pneumatic threadcontrol means for the reserve bobbin weft ends vvof a loom having an electric circuit to be closed upon failure of the control means, a source of subatmospheric pressures, a pneumatic thread 'collector in which subatmospheric pressures are created by said source, a pneumatic thread holder for the weft ends normally pneumatically disconnected from said collector but periodically connected pneumatically to the collector for brief intervals, and pneumatically controlled circuit closing means for said circuit responsive to pneumatic pressures within said collector and normally maintaining the circuit open but effective to close said circuit upon failure of the control means due to absence of subatmospheric pressures within the collector for a period of time longer than one of said intervals but ineffective to close the circuit when said collector and holder are pneumatically connected during said intervals.

VICTOR F. SEPAVICH.

No references cited. 

